Five trials (n=525 eyes) meeting the inclusion criteria were identified; data from three trials (n=232 eyes) were included in the meta-analysis. Trial quality was graded either B or C in all trials; no definition of grades was provided but trial quality was discussed narratively. The process of randomisation was described in one trial and allocation concealment was not described in any trial. Outcome assessment was adequately blinded in three trials and partially blinded in two. The review authors described quality as adequate.
Anti-vascular endothelial growth factor (anti-VEGF) treatment resulted in an improvement in visual acuity of -0.17 (95% CI -0.23 to -0.10; n=234 eyes) and in central macular thickness of -84.69μm (95% CI -117.09 to -52.30).
One trial assessed three doses of pegaptanib (0.3mg, 1mg and 3mg); similar effects on visual acuity and central macular thickness were observed regardless of which pegaptanib arm was included in the meta-analysis.
Two trials of patients treated with anti-VEGF in combination with intravitreal triamcinolone (n=140 eyes) showed slightly larger improvements in visual acuity and central macular thickness. No significant increases in complications were reported from anti-VEGF treatment.
Substantial heterogeneity was observed between trials both for the assessment of visual acuity (I2 65% to 81% depending on pegaptanib arm included) and for central macular thickness (I2 49% to 73%). Forest plots suggested the treatment effects were largely consistent, so the results were pooled regardless of heterogeneity.